Whoso would be a man, must be a nonconformist. He who would gather immortal palms must not be hindered by the name of goodness, but must explore if it be goodness. Nothing is at last sacred but the integrity of your own mind.

Ralph Waldo Emerson (1803-1882) American essayist, lecturer, poet

Essay (1841), “Self-Reliance,” Essays: First Series, No. 2
    (Source)

This essay was inspired by his reading of Walter Savage Landor in 1833, with passages pulled from his lecture "Individualism," last in his course on "The Philosophy of History" (1836–1837), with other passages from the lectures "School," "Genius," and "Duty" in his course on "Human Life" (1838–1839).